docs: def find_module(module, path=None, imp=None):
      """Version of :func:`imp.find_module` supporting dots."""
      if imp is None:
          imp = importlib.import_module
      with cwd_in_path():
          if "." in module:
              last = None
              parts = module.split(".")
              for i, part in enumerate(parts[:-1]):
                  mpart = imp(".".join(parts[:i + 1]))
                  try:
                      path = mpart.__path__
                  except AttributeError:
                      raise NotAPackage(module)
                  last = _imp.find_module(parts[i + 1], path)
              return last
          return _imp.find_module(module)